1. Field of the Invention
The present invention relates to an organic light emitting diode display.
2. Description of the Related Art
An organic light emitting diode display is a self-light emitting display device displaying an image by using an organic light emitting diode emitting light. Since the organic light emitting diode display, unlike a liquid crystal display, does not require a separate light source, a thickness and a weight thereof may be relatively reduced. Furthermore, since the organic light emitting diode display has high quality characteristics such as low power consumption, high luminance, and a high reaction speed, the organic light emitting diode display receives attention as a next generation display device of a portable electronic device.
The organic light emitting diode includes two electrodes and a light emitting layer positioned therebetween, electrons injected from one electrode and holes injected from the other electrode are bonded to each other in the light emitting layer to form an exciton, and light is emitted while the exciton discharges energy.
In the organic light emitting diode, it is important to increase light emitting efficiency and improve a life span.
In order to increase the life span of the organic light emitting diode, a structure where charge loading layers, such as the light emitting layer, a hole injection layer, and an electron injection layer, are laminated in plural to increase luminance to a current by 2 to 3 times has been developed.
However, since units formed of a hole loading layer, the light emitting layer, and an electron loading layer should be repeatedly laminated in order to laminate loading layers constituting organic light emitting layers in plural, there is a problem in that a deposition process and costs are increased.
Furthermore, there is a problem in that a light emitting area is reduced due to overlapping of the organic light emitting layers or light emitted from the organic light emitting layers laminated on an upper portion is reflected by the organic light emitting layers laminated on a lower portion to reduce efficiency.
The above information disclosed in this Background section is only for enhancement of an understanding of the background of the invention, and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.